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Blue tongue is a non-contagious insect borne viral disease of sheep, cattle and wild ruminants.

How is it transmitted? Blue tongue virus is transmitted to animals by the bite of infected midges (Culicoides species). These insects are often found around water and so animals that are in the vicinity are at risk of being bitten.

Culicoides are around water
Culicoides are around water

Sheep near water
Sheep near water become infected with Blue Tounge when bitten by Culicoides

What are the signs in animals?
Infected sheep may die before signs have time to develop. Less severely affected sheep show edema of lips, nose, face, submandibular area, eyelids, and occasionally ears. The name ‘Blue tongue’ arises from the congestion of mouth and tongue that gives a bluish appearance. Sheep may show lameness due to the swelling and inflammation at the coronary bands. Loss of the fleece (wool break) may also result from blue tongue infections.

blueish apperance in a sheeps mouth
'Bluish' apperence in a mouth
feet lesions
Feet with coranary band swelling

edema in ram
Facial edema on sheep infected with blue tounge swollen ram lips
Edema in the lips of a ram infected with blue Tounge

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